"Thank you for my team," said Hsieh, who reached the second round at Roland Garros for only the second time. "Merci beaucoup for the match today."

Hsieh will next play American Taylor Townsend, who beat Japanese qualifier Miyu Kato 6-4, 6-0.

Spanish veteran Verdasco also caused a major upset yesterday when he eliminated in-form Alexander Zverev of Germany 6-4, 3-6, 6-4, 6-2 in the first round after their game had been interrupted at one set all on Monday.

The 33-year-old clay-court specialist outmuscled the German ninth seed when play resumed yesterday, with Zverev having lost his momentum from a day earlier when he had grabbed the second set and looked in complete control.

Verdasco will play France's Pierre-Hugues Herbert for a place in the last 32.

Elsewhere in the women's draw, in-form Ukrainian Elina Svitolina moved swiftly into the second round yesterday, easing through a potentially tricky encounter against Yaroslava Shvedova with a 6-4 6-3 victory.

The fifth seed, one of the pre-tournament favourites after winning the Rome claycourt tournament, was just a cut above her Kazakh opponent, who has reached the quarter-finals twice at Roland Garros.

"I felt good on court, played the important points well. Winning a big title just before coming here gave me a lot of confidence and I look forward to my next match," said Svitolina.